基于梁-拱复合受力机制的高强混凝土梁受剪分析模型  

Shear analysis model of high-strength concrete beams based on beam-arch action mechanism

作　　者：祖坤 熊二刚[3] 罗斌[1,2] 梁兴文[4] ZU Kun;XIONG Ergang;LUO Bin;LIANG Xingwen(Key Lab of Concrete and Prestressed Concrete Structures(Southeast University),Ministry of Education,Nanjing 211189,China;School of Civil Engineering,Southeast University,Nanjing 211189,China;School of Civil Engineering,Chang’an University,Xi’an 710061,China;School of Civil Engineering,Xi’an University of Architecture and Technology,Xi’an 710055,China)

机构地区：[1]混凝土及预应力混凝土结构教育部重点实验室(东南大学),南京211189 [2]东南大学土木工程学院,南京211189 [3]长安大学建筑工程学院,西安710061 [4]西安建筑科技大学土木工程学院,西安710055

出　　处：《哈尔滨工业大学学报》2022年第11期78-87,共10页Journal of Harbin Institute of Technology

基　　金：国家自然科学基金(11673039,51808046);陕西省重点研发计划(2021SF-461)。

摘　　要：为研究高强混凝土梁构件斜截面受剪力学性能,通过分析高强混凝土梁发生剪切破坏时剪跨段内剪力传递路径,提出基于梁作用和拱作用来考虑高强混凝土对梁构件受剪承载力的贡献,箍筋贡献项采用简化修正压力场理论计算,同时考虑尺寸效应的影响,通过混凝土和箍筋两部分贡献项相叠加建立了集中荷载作用下高强混凝土梁受剪承载力计算公式,该公式物理意义清晰明确,综合考虑了混凝土强度、剪跨比、相对剪压区高度、纵筋配筋率、配箍率以及尺寸效应等因素的影响。利用收集到的207根有腹筋高强混凝土梁试验数据对本文受剪分析模型公式预测精度进行验证,并与GB 50010—2010规范、ACI 318-19规范、EN 1992-1-1:2004规范、Zararis公式、Zsutty公式计算结果进行比较。结果表明:本文所提受剪分析模型能够真实反映梁构件斜截面受剪破坏机理,较好地预测高强混凝土梁受剪承载力,对受剪参数的大范围变化不敏感且随受剪参数的大范围变化,预测精度无明显相关性。根据对比结果,本文基于梁-拱复合受力机制和简化修正压力场理论所建立的受剪分析模型可用于高强混凝土梁受剪承载力计算,且具有良好的预测精度和一致稳定性。The shear transfer pathway in the shear span of high-strength concrete beam was analyzed under shear failure to investigate the shear mechanical property of the inclined section of high-strength concrete beam.The contribution of high-strength concrete to the shear capacity of beam was considered based on the beam action and arch action.The stirrup contribution was determined by using the simplified modified compression field theory,and the influence of size effect was taken into consideration.Through the combination of concrete and stirrup terms,the calculation model for the shear capacity of high-strength concrete beam under concentrated load was established,which has a clear and reasonable physical significance.The effects of concrete strength,shear-span ratio,relative depth of shear compression zone,ratio of longitudinal reinforcement,ratio of stirrup,and size effect were comprehensively analyzed.In addition,the test data of 207 high-strength concrete beams with web reinforcement were employed to evaluate the proposed calculation model,and compared with the prediction results of GB 50010—2010,ACI 318-19,EN 1992-1-1:2004,Zararis formula,and Zsutty formula.Results show that the proposed model could reflect the shear failure mechanism of the inclined section of beam and predict the shear capacity of high-strength concrete beams.Besides,the model was less sensitive to the wide range variation of shear parameters,and the prediction accuracy had no obvious correlation.Thus,in combination with beam-arch action and simplified modified compression field theory,the proposed shear model can be used to calculate the shear capacity of high-strength concrete beams with high accuracy and stability.

关 键 词：钢筋混凝土梁 高强混凝土 剪切破坏 分析模型 受剪承载力 

分 类 号：TU375.1[建筑科学—结构工程]